On 6 Nov, 2014, at 20:16 , Sanjeev Gupta <[email protected]> wrote: > Anyone who wishes to believe 60 secs always to a minute can continue to do > so. Anyone who needs the extra accuracy (time-nuts, astronomers, pedants, > old men like me) will learn the fact that a minute is not always 60 secs. > Anyone who is unwilling to learn this should not be pointing the scope on Mt > Palomar anyway.
So you'd be okay with a hectosecond that wasn't 100 seconds? The problem with the UTC minute is that it is a polysemous use of the word "minute". In most contexts the word still means precisely 60 seconds, as it always did. An SI-compatible minute is always 60 seconds and 1/60 of something else. The constant 86400 that keeps appearing in equations is inexplicable without that definition. A Julian date with many digits to the right of the decimal point can have those digits unambiguously expressed as an hh:mm:ss form for pretty much any timescale except UTC, where the meaning of the digits becomes a bit fuzzy. The UTC definition of "minute" isn't more accurate, it is just a different definition of the same word. I realize, however, that an argument about polysemy isn't a particularly strong one. Avoiding polysemy is a benefit which needs to be balanced against its cost, and making up new words to describe the new definition of the units of UTC (and civil time) would have had a high cost compared to just redefining the traditional units to be different in that context. I would just point out that the argument that a new definition of our civil timescale to retain SI seconds but eliminate leap seconds should have a new name to avoid making "Universal Time" polysemous is one that seems very similar since there would be a price to pay for not continuing to call the redefined universal timescale UTC. I'm not sure what I think about that trade off, but I do find it a little inconsistent for a person to strenuously object to that polysemy while simultaneously arguing that the older one is perfectly acceptable. You could learn the fact that UTC is no longer as close to mean solar time as it once was if you needed the extra accuracy. Most people probably won't need to bother. Dennis Ferguson _______________________________________________ LEAPSECS mailing list [email protected] https://pairlist6.pair.net/mailman/listinfo/leapsecs
